1. Technical Field
The present invention disclosed herein relates to a semiconductor memory device, and more particularly, to a memory system and a method of accessing a semiconductor memory device.
2. Description of Related Art
A semiconductor memory device is a storage device that can store data and read the stored data when required. Semiconductor memory devices may be mainly classified into volatile memory devices and nonvolatile memory devices.
Volatile memory devices loose stored data when power supply is interrupted. In contrast, nonvolatile memory devices retain stored data even if power supply is interrupted. Examples of nonvolatile memory devices are a read only memory (ROM), a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable PROM (EEPROM), a flash memory device, a phase change random access memory (PRAM), a magnetic RAM (MRAM), a resistance RAM (RRAM), a ferroelectric RAM (FRAM), and so forth.